Apparatus for making inner tubes



Feb. 28, 1928.

l ,660,343 c. E. LOWE APPARATUS FOR MAKING INNER TUBES Filed March '7. 1927 T/g. 6 y

C/yde E. Lowe Inveno.

Patented Feb. as, 192s. 'y Y l l i 2 1,660,343 UNITEDSTATES gPArENr-oFFl-cc.-

` GLYDE E. ILoWE, or EAST CLEVELAND, omo.

kAPPARATUS Eon MAKING INNER 'runasv Application led March 7,1927.' 'Serial No.'173,359.

This invention relates to the manufacture shape to afford the desired taper at each end of inner tubes for pneumatic vehicle tires ofthe tube. To this en d the ring is preferand has for its object the provisionfof sim- Vably'made of a band of flexible metal, such ple, inexpensive and reliable `mechanism as sheet steel, fashioned to the shape of a which shall perform the combined function wideespreading V as illustrated in Figs. 4

of preventing admission of pressure fluid and 5,-'the'apex 3 of the V facinginwardly beneath the tube,of trimming the tube to andthe sides 4*'4 diverging therefrom, and

lthe proper length, and of beveling or skiv- "hence from the walls of the mandrel to which ing the' ends of the tube preparatory to y the device is applied. The ends ofthe ring 65 splicing. In the manufacture of these'innerl Overlap at fone end as illustrated at 5,' and c tubes it is customary to buildor locate the suitable means-are provided toconstrluct this raw rubber tube on a form called a mandrel ring upon the tube to which it is applied. and subject the same to pressure duringthe In the form shown in Figs. land 3 these heat-treating operation whereby the rubmeans comprise a pair of rigid ears 6 6 car- 70v ber is cured. In order to secure a 4proper l'led bythe respective endsof thering, havcompactness of the tube-wall it is necessary lng a. clamping bolt 7 pivoted in one ear-and to exclude the pressure fluid from penetratdetachablyengaging the other ear through ing between the tube and mandrel during the the agency of'a thumb nut'8 and rocker 9. curing operation; and after curing has beenv The meeting endsy of the ring are so fash- 7"` completed the tube is withdrawn from the loned and beveled as to slide smoothly over mandrel and the two ends spliced together Bach other with a minimum of gouging effect. which requires that the ends of the tube be In the form of the linvention shown in Figs. Skived or beveled which has heretofore re- 2 and 7, the ears are set further apart and quired, at least in many cases, a special ina tension spring l() connected therebetween dependent operation. By the use of the S0 as to exert a continuous constrictingefect apparatus described in this application all upon the ring during the curing operation. these things can be done reliably and by Preferably this spring 'is pivoted at one end single operation, and the apparatus reused and detachably secured at the other as by indefinitely the ball ll, fitting a socket 12 provided in 85 In the drawings accompanying and formone of the ears, thus enabling all tension Vto ing a part of this application Fig. 1 is a be removed` during the application and reperspective view of one end of a mandrel Inoval of the clamp. According to another and uncured tube illustrating the use of my form of the invention shown in Figs. 5 and invention; Fig. 2 is a perspective view show- 6 the ears are omitted and a garter spring 90 ing the use of my improvements in combina 13 caused toencircle the ring in the angle tion with a curved type ofI mandrel; Fig. 3 defined by the two sides ofv the V. 1 In all is a side view of one of my improved throtcases it is necessary to choose the angles so tling and skiving rings; Fig. 4 is a longithat the apex 3 may form an edge suiiiciently tudnal sectional view through a tube curing sharp to cut through the rubber gum. f

' apparatus including one of my rings; Figs. After the tube lhas been applied tothe 5 and 6 are sectional views through a modimandrel a ring is applied adjacent to each lied form of ring; and Fig. 7 is a detail View end of the tube and gripped thereon in such showing the type of ring illustrated in wise as to prevent the penetration of pres- Fig. 2.

In the manufacture of an inner tube a during the curing operation. With the mandrel l of suitable length, diameter, and form of thev invention shown in Figs. l to cross-section has applied thereto or built 4, inclusive, the nut 8 is screwed down sulithereon a tube 2 of raw rubber compound. ciently at the outset to bring the cutting I have illustrated hollow metal mandrels of edge of the V substantially into engagement circular cross section, straight in Fig. 1 and with the mandrel thereby substantially sevarcuate in Fig. 2, though it will be 'underering the extremity of the tube from the stood that other materials and shapes can body thereof; in the form of the invention be employed. f shown in Figs. 2, 5, 6, and 7 the initial pres- To each end of the tube I apply a ring sure is not sufficient to effect this, but the having a peripheral shape to fit closely the ring gradually contracts upon the tube as exterior of the mandrel and of a transverse the latter softens under the heat of the cursure fluid between ythe tube and mandrel 100y seldom that the ing and `effects the severing prior to the end of the operation.y The slantinglivalls'of the ringimposesufficient pressure on the rubber to prevent accidental displacement of the same or entrance of pressureV fluidV and also afford the desired slive `for splicing. It is end portion is ered from the body of the tube by this apparatus but the same can ordinarily be pulled away by the "fingers leaving `a su'tlicientlyT clean -cut for the next operation.-

lt is not important that the trimming for Waste end be skived, but it is desirable that each ringbe symmetrical7 both to facilitate its application, to reduce errors, and to overcome any tendency to slip or drift to one side. However, it is notstrictly necessary that `the tivo sides be symmetrical or that the cutting edge be in the center,` andother "if changes can be :made within the scope of my inventive ideas Having thus I claimais: 4 Y p 1L In tube `curing apparatus, the combinadescribedmy l invention what tionfivitha n mandrel adapted to receive a raw tube,A of aconstrictible metal clamp adaptedl tolembrace said mandrel andhavturned `inivardly7 ingalperipheral contoun similar to that of the mandrel and having thecross section of a Wide spreading V defining a cutting edge and two taperingf surfaces.

2." A combinedA clamping, cutting, and skivingdevice for tire tube manufacture,

consisting eta metal strip having the cross sectionof a avide spreading V `:termed With its ends overlapping and the apex o the V `turnedinwardly,.to define a cutting edge,

and means oreonstricting said dev-ice upon a mandrelto severa tube thereon Aandslive thetube end.` n v n i 3.A` combined clamping, cutting and skivingldevice for tirel tube manufacture, consisting ,of a metal striphaving the cross sectionmt ahwide'- spreading Vwformed With its ends Voverlapping 'and the apex of the V to define` a` and spring uneansi for constantly exerting a constrcting action yupon said device during the i curingizoperationvwhereby the tube is severed and skived. t n

In testimony whereof I hereunto atx my signature` n A cnvnnin Lown cutting edge,` 

